package com.capricorn;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.Animation;
import android.view.animation.Animation.AnimationListener;
import android.view.animation.AnimationSet;
import android.view.animation.Interpolator;
import android.view.animation.LinearInterpolator;
import android.view.animation.OvershootInterpolator;
import android.view.animation.RotateAnimation;

import com.bmob.im.demo.widget.R;

public class RayLayout extends ViewGroup {

    /**
     * children will be set the same size.
     */
    private int mChildSize;

    /* the distance between child Views */
    private int mChildGap;

    /* left space to place the switch button */
    private int mLeftHolderWidth;

    private boolean mExpanded = false;

    public RayLayout(Context context) {
        super(context);
    }

    public RayLayout(Context context, AttributeSet attrs) {
        super(context, attrs);

        if (attrs != null) {
            TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.ArcLayout, 0, 0);
            mChildSize = Math.max(a.getDimensionPixelSize(R.styleable.ArcLayout_childSize, 0), 0);
            a.recycle();

            a = getContext().obtainStyledAttributes(attrs, R.styleable.RayLayout, 0, 0);
            mLeftHolderWidth = Math.max(a.getDimensionPixelSize(R.styleable.RayLayout_leftHolderWidth, 0), 0);
            a.recycle();

        }
    }

    private static int computeChildGap(final float width, final int childCount, final int childSize, final int minGap) {
        return Math.max((int) (width / childCount - childSize), minGap);
    }

    private static Rect computeChildFrame(final boolean expanded, final int paddingLeft, final int childIndex,
                                          final int gap, final int size) {
        final int left = expanded ? (paddingLeft + childIndex * (gap + size) + gap) : ((paddingLeft - size) / 2);

        return new Rect(left, 0, left + size, size);
    }

    /**
     * refers to {@link LayoutAnimationController#getDelayForView(View view)}
     */
    private static long computeStartOffset(final int childCount, final boolean expanded, final int index,
                                           final float delayPercent, final long duration, Interpolator interpolator) {
        final float delay = delayPercent * duration;
        final long viewDelay = (long) (getTransformedIndex(expanded, childCount, index) * delay);
        final float totalDelay = delay * childCount;

        float normalizedDelay = viewDelay / totalDelay;
        normalizedDelay = interpolator.getInterpolation(normalizedDelay);

        return (long) (normalizedDelay * totalDelay);
    }

    private static int getTransformedIndex(final boolean expanded, final int count, final int index) {
        return count - 1 - index;
    }

    private static Animation createExpandAnimation(float fromXDelta, float toXDelta, float fromYDelta, float toYDelta,
                                                   long startOffset, long duration, Interpolator interpolator) {
        Animation animation = new RotateAndTranslateAnimation(0, toXDelta, 0, toYDelta, 0, 720);
        animation.setStartOffset(startOffset);
        animation.setDuration(duration);
        animation.setInterpolator(interpolator);
        animation.setFillAfter(true);

        return animation;
    }

    private static Animation createShrinkAnimation(float fromXDelta, float toXDelta, float fromYDelta, float toYDelta,
                                                   long startOffset, long duration, Interpolator interpolator) {
        AnimationSet animationSet = new AnimationSet(false);
        animationSet.setFillAfter(true);

        final long preDuration = duration / 2;
        Animation rotateAnimation = new RotateAnimation(0, 360, Animation.RELATIVE_TO_SELF, 0.5f,
                Animation.RELATIVE_TO_SELF, 0.5f);
        rotateAnimation.setStartOffset(startOffset);
        rotateAnimation.setDuration(preDuration);
        rotateAnimation.setInterpolator(new LinearInterpolator());
        rotateAnimation.setFillAfter(true);

        animationSet.addAnimation(rotateAnimation);

        Animation translateAnimation = new RotateAndTranslateAnimation(0, toXDelta, 0, toYDelta, 360, 720);
        translateAnimation.setStartOffset(startOffset + preDuration);
        translateAnimation.setDuration(duration - preDuration);
        translateAnimation.setInterpolator(interpolator);
        translateAnimation.setFillAfter(true);

        animationSet.addAnimation(translateAnimation);

        return animationSet;
    }

    @Override
    protected int getSuggestedMinimumHeight() {
        return mChildSize;
    }

    @Override
    protected int getSuggestedMinimumWidth() {
        return mLeftHolderWidth + mChildSize * getChildCount();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(getSuggestedMinimumHeight(), MeasureSpec.EXACTLY));

        final int count = getChildCount();
        mChildGap = computeChildGap(getMeasuredWidth() - mLeftHolderWidth, count, mChildSize, 0);

        for (int i = 0; i < count; i++) {
            getChildAt(i).measure(MeasureSpec.makeMeasureSpec(mChildSize, MeasureSpec.EXACTLY),
                    MeasureSpec.makeMeasureSpec(mChildSize, MeasureSpec.EXACTLY));
        }
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        final int paddingLeft = mLeftHolderWidth;
        final int childCount = getChildCount();

        for (int i = 0; i < childCount; i++) {
            Rect frame = computeChildFrame(mExpanded, paddingLeft, i, mChildGap, mChildSize);
            getChildAt(i).layout(frame.left, frame.top, frame.right, frame.bottom);
        }

    }

    private void bindChildAnimation(final View child, final int index, final long duration) {
        final boolean expanded = mExpanded;
        final int childCount = getChildCount();
        Rect frame = computeChildFrame(!expanded, mLeftHolderWidth, index, mChildGap, mChildSize);

        final int toXDelta = frame.left - child.getLeft();
        final int toYDelta = frame.top - child.getTop();

        Interpolator interpolator = mExpanded ? new AccelerateInterpolator() : new OvershootInterpolator(1.5f);
        final long startOffset = computeStartOffset(childCount, mExpanded, index, 0.1f, duration, interpolator);

        Animation animation = mExpanded ? createShrinkAnimation(0, toXDelta, 0, toYDelta, startOffset, duration,
                interpolator) : createExpandAnimation(0, toXDelta, 0, toYDelta, startOffset, duration, interpolator);

        final boolean isLast = getTransformedIndex(expanded, childCount, index) == childCount - 1;
        animation.setAnimationListener(new AnimationListener() {

            @Override
            public void onAnimationStart(Animation animation) {

            }

            @Override
            public void onAnimationRepeat(Animation animation) {

            }

            @Override
            public void onAnimationEnd(Animation animation) {
                if (isLast) {
                    postDelayed(new Runnable() {

                        @Override
                        public void run() {
                            onAllAnimationsEnd();
                        }
                    }, 0);
                }
            }
        });

        child.setAnimation(animation);
    }

    public boolean isExpanded() {
        return mExpanded;
    }

    public void setChildSize(int size) {
        if (mChildSize == size || size < 0) {
            return;
        }

        mChildSize = size;

        requestLayout();
    }

    /**
     * switch between expansion and shrinkage
     *
     * @param showAnimation
     */
    public void switchState(final boolean showAnimation) {
        if (showAnimation) {
            final int childCount = getChildCount();
            for (int i = 0; i < childCount; i++) {
                bindChildAnimation(getChildAt(i), i, 300);
            }
        }

        mExpanded = !mExpanded;

        if (!showAnimation) {
            requestLayout();
        }

        invalidate();
    }

    private void onAllAnimationsEnd() {
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            getChildAt(i).clearAnimation();
        }

        requestLayout();
    }

}
